Method of making bungs



1941- c. E. SHEPARD 2,248,417

METHOD OF MAKING BUNGS Original Filed May 3', 1937 I "KY1 10 I I I Illlll HHHI I Patented July 8, lgl

METHOD OF MAKING BUNGS Original application May 3,

1937, Serial No.

140,353. Divided and this application May 20. 1939, Serial No. 274,681

1 Claim.

This application is a division of my copending application Serial No. 140,353, filed May 3, 1937, Patent No. 2,200,583.

The above-identified copending application relates to a novel method for making bungs having a body portion formed of sheet metal and a transverse handle member located within the body. The present invention relates to a different method for making a similar bung. The invention will be readily understood from the following description, taken in conjunction with the accompanying drawing, in which:

Fig. 1 is an elevational view, partly in cross section, of a set of dies suitable for making the improved bung body;

Fig. 2 is an elevational view, partly in cross section, of the dies shown in Fig. 1 with the view in Fig. 2 taken at right angles to that of Fig. 1;

Fig. 3 is a plan view of the blank from which the body of the bung is formed;

Fig. 4 is a plan view of a preferred form of a wrench engaging bar;

Fig. 5 is a plan view of the bung body formed with the wrench engaging bar therein;

Fig. 6 is a front elevation, partly in section, of the bung body shown in Fig. 5; and

Fig. 7 is an elevational view, partly in section, of the completed bung.

Referring to Figs. 1 and 2 of the drawing, the upper die consists of a ring Iii, the inside diameter I2 of which corresponds with the outside diameter and shape of the bung body desired. Within this ring [9 is an ejecting member M, which serves to push the formed bung body from the upper die following the forming operation. The lower die consists of a ring l6, which has a slightly depressed annular seat l8 to receive a circular blank 20 from which the bung body is to be formed. The ring l6 rests upon vertical spaced pins 22 supported in turn by suitable compression means, not shown. The ring it surrounds a punch 24 of the shape and size of the inside of the bung body desired, excepting that it is provided with a transverse slot 26 extending diametrically across its face. This slot has a width and depth slightly greater than the width and depth of the wrench engaging bar 28.

These dies operate in a manner to be discussed presently to produce a bung body having a wrench engaging bar therein, as shown in Figs. 5 and 6. This bung body consists of a cup-shaped portion having a relatively flat bottom portion 30, a cylindrical wall 32 rising therefrom, and an outwardly projecting annular flange 34 at the upward end of the cylindrical wall. The inside surface of the cup-shaped bung body provides a cylindrical opening 35 within which the cross bar 28 is secured. This cross bar preferably has relatively sharp corners 38, which are embedded sufficiently within the walls of the bung body to hold the bar rigidly in place; that is, the bar is somewhat longer, at least at its sharp edges, than the cord of the arc across which it extends. Although I prefer to make the cross bar as shown, it will be understood that this bar may be made of folded sheet metal and the ends may be shaped differently than shown in Fig. 4. In order to insure the bar being held rigidly in place within the bung body, I prefer to make the bar of hardened or harder metal than the blank 29.

According to the method comprising this invention, the body of the bung is formed by drawing the blank 20 around the ends of the cross bar 28 and shaping the metal in the blank into the cup just described, all in one operation. To accomplish this, the bar 28 is centrally located within the slot 26 in the punch 24 with its ends projecting somewhat from the ends of the slot. The blank 20 is then located within the annular seat I8, andthe upper die is caused to approach the lower die. As the upper die telescopes over the lower die, the metal in the blank 20 is caused to flow down around the punch 24 and aroundthe ends of the bar 23, which project from the surface of the punch. When the upper die reaches the bottom of its stroke, the bung body will be completely formed and the metal in the blank will have flowed around the ends of the bar 28, thereby securely embedding these ends within the metal of the cup-shaped body. As the upper die recedes from its lowermost position, the bung body is lifted from the lower die and carries with it the cross bar 28. When the press reaches the upper end of its stroke, the bung body with the bar therein will have been forced from the upper die member by the ejecting member I4.

The bung body is then as shown in Figs. 5 and 6. After being removed from the dies, this bung body is threaded at in upon its outer cylindrical surface and equipped with a gasket (not shown) beneath a shoulder 42 provided on the lower surface of the flange 3:3. The bung is then ready for use.

It will be seen that from the relatively simple blank 29 and bar 28 a complete bung body equipped with a wrench engaging bar and ready for machining can be manufactured complete in one press operation.

Having thus described my invention, what I metal in the blank is drawn around the end of the male die and caused to flow around the ends of said bar to form the bottom and cylindrical side walls of a bung and to embed the ends of the bar in the cylindrical side wall, said dies also simultaneously forming an outwardly turned flange normal to said side wall, and cutting a thread on the outside of said bung.

CLEO E. SHEPARD. 

